Illuminator



ivi-rch l?, i936. D. J. BILLER ILLUMINATOR Filed Feb. le, 19'54 HAS,QTroeN Ks.,

UNITED STATES PATENT QFFEQE ILLUMINA'roR David J. Biller, St. Louis,Mo., assignor to Day- Brite Reiector Company, St. Louis, Mo., a.corporation of Missouri Application February 16, 1934, Serial No.'711,493

4 Claims.

This invention relates principally to devices for illuminating the sidesof passageways, particularly for illuminating book stacks, stock bins,filing cabinets and the like which are commonly arranged on either sideof passageways. The principal object of the present invention is toprovide a simple and economical illuminator which will provide an evendispersion of the light from top to bottom of the sides of thepassageway, and which will minimize glare. The invention consists in theilluminating device and in the construction, combinations andarrangements of parts hereinafter described and claimed,

In the accompanying drawing, which forms part of this specification andwherein like symbols refer to like partsl wherever they occur,

Fig. l is a View, partly in vertical section and partly in sideelevation, of an illuminating device embodying my invention, the devicebeing shown attached to an outlet box mounted in a ceiling, dispersionand reflection of the light rays from typical points on the reflectorshade and disk being indicated by dotted lines;

Fig. 2 is a horizontal section on the line 2--2 in Fig. l;

Fig. 3 is a horizontal section on the line 3 3 in Fig. l;

Fig. 4 is a fragmentary plan View of the middle portion of the reectordisk;

Fig. 5 is a fragmentary plan View of the middle portion of the reectorshade;

Fig. 6 is a fragmentary vertical section, showing the manner of'fastening the disk reector to the outlet box; and

Fig. 7 is a vertical cross-section through a portion of a library stackroom with the illuminating device sustained by the ceiling above thepassageway between the book stacks, the dotted lines indicating thevarious directions in which the light rays are dispersed.

Referring to the accompanying drawing, my invention is shown inconnection with a source of light comprising an electric light bulb Amounted in a suitable socket B disposed beneath a suitable outlet box Cthat is attached to the ceiling of a library stack room midway of thepassageway D formed by two lines of book stacks E.

The light from the electric light bulb is distributed by means of areflector disk F located above the light bulb A and a reiiector shade Gthat surrounds said light bulb below said refiector disk. The reiiectordisk F is of greater diameter than the reflector shade G; and the lowersurface of said reflector disk and the inner and outer surfaces of saidreflector shade are provided with a suitable light reflecting coveringsuch as white porcelain enamel.

'Ihe reflector disk F is removably secured flatwise'to the underside ofthe outlet box C by means of diametrically opposed screws l. The screwsI are located outside of the reflector shade G and extend upwardlythrough openings 2 in the reflector disk F and are threaded intoinwardly extending ears 3 at the lower edge of the outlet box` C. Thescrew receiving openings 2 in the reflector disk F are in the form ofkeyhole slots so as to permit said disk to be attached to and detachedfrom the outlet box C without removing the screwsl.

The reflector shade G is removably secured flatwise to the underside ofthe reflector disk F means of diametrically opposed screws 4 that extendupwardly through openings 5 in the top of said reflector shade and arethreaded into said reflector disk. The openings 5 are in the form ofkeyhole slots so as to permit the reflector shade to be detached fromthe reflector disk without removing the screws ll.

The light socket B has a base portion 6 located within the upper portionof the reflector shade G and an upper portion l of reduced diameter thatextends upwardly through central openings 8 and 9 provided therefor inthe top of said shade and in the reflector disk F. The enlarged baseportion 6 of the socket B is removably secured to the underside of thetop wall of the reflector shade G by means of diametrically opposedbolts l0. These bolts extend upwardly through registering holes providedtherefor in the base portion of the socket and in the top of thereflector shade and have nuts ll threaded on their'upper ends andbearing against the top of said shade. The bolt holes I2 in the top ofthe reflector shade are located intermediate between the keyhole slots 5therein; and the socket receiving opening 9 in the reflector disk isenlarged, as at 9a, to accommodate the nuts l l for the bolts I0.

By the arrangement above described, the illuminator may be readilymounted on and dismounted from the outlet box. To install theilluminator, the socket B is secured to the top of the reflector shade Gby means of the bolts I0, the reflector disk F is secured to the bottomof the outlet box byv means of the screws l. The electric wires are thenfastened to the light socket, after which the reflector shade is securedto the underside of the reflector disk by means of the screws 4. Indismounting the illuminator, the reflector shade and the reflector diskmay be removed without removing the fastening screws l therefor bybringing the heads of said screws into register with the enlarged endsof the keyhole slots 2.

The reflector shade comprises a downwardly opening bell-shaped bodyportion having a lower portion I3 of relatively steep taper, an upperportion I4 of slightly less width and slightly steeper taper, and arelatively narrow intermediate portion I5 which tapers less steeply thanthe wider upper and lower portions. The upper portion I4 is providedwith four circumferentially spaced openings I6 that are separated bypairs of diametril cally opposed webs II located respectivelylongitudinally of and at right angles to the axis of the aisle.

With the illuminator mounted on the ceiling above the passageway, asshown in Fig. 7, some of the rays from the incandescent light bulb A areprojected downwardly and outwardly from the mouth of the reflector shadeG, the dash lines indicating the upper limit of the rays issuingdirectly or by reflection from the mouth of said shade. Thus the uppershelves are not illuminated by these rays. As shown in dotted lines inFigs. 1 and 7, some of the light rays are projected outwardly throughthe openings I6 in the upper portion I4 of the reflector shade and serveto light the uppermost shelves of the book stacks.

ther of the rays projected through the openings I5 strike the undersideof the reflector disk and are deflected downwardly and outwardly towarintermediate shelves. Some of the light rays reflected by the reflectordisk are again reflected at various oblique angles by the differentlytapered outer sides of the reflector shade and thus result in a furtherdispersion of the light over the upper book shelves. As the light raysare dispersed around the entire periphery of the illuminator, theyextend longitudinally and angularly as Well as transversely, so thatlong stretches of the sides of the passageway are illuminated by asingle fixture.

The above illuminator produces an even dispersion of the light from topto bottom of the sides of the passageway and it minimizes the glare. ltalso secures a maximum dispersion of the light rays lengthwise of saidsides, thus permitting a maximum spacing of the illuminators.

What I claim is:

l. An illuminator comprising an incandescent light bulb, a sockettherefor, an outlet box, a reilector disk removably secured ilatwise tothe underside of said outlet box, a reflector shade surrounding saidbulb and having a flat top wall which is removably secured flatwise tothe underside of said reflector disk, and means for removably securingsaid socket to the underside of the top wall of said reflector shade.

2. An illuminator comprising an incandescent light bulb, a sockettherefor, an outlet box, a reflector disk secured tothe underside ofsaid outlet box, a reflector shade surrounding said bulb and removablysecured to the underside of said reflector disk, and means for removablysecuring said socket to the top of said reflector shade, said disk andsaid shade being provided with central openings through which the upperportion of said socket extends, the upper portion of said reector shadebeing provided with a series of circumferentially spaced openings, thelower portion having a relatively steep taper and the portionintermediate between said openings and said lower portion having aslightly steeper taper.

3. An illuminator of the overhead exposed bulb type comprising adepending light bulb, a socket therefor, and a downwardly openingbell-shaped shade of opaque material surrounding said bulb and havinginterior and exterior light reflecting surfaces, said shade having aflat top wall for sustaining said socket, a lower portion of relativelysteep taper and an intermediate portion which tapers less steeply thansaid lower portion, said intermediate portion being spaced below saidflat top wall and rigidly connected to the outer edge thereof by aseries of circumferentially spaced webs.

4. An illuminator of the overhead exposed bulb type comprising adepending light bulb, a socket therefor, and a downwardly openingbell-shaped shade of opaque material surrounding said bulb L and havingan interior light reflecting surface, said shade having a flat top wallfor sustaining said socket, a lower portion of relatively steep taperand an intermediate portion which tapers less steeply than said lowerportion, said intermediate portion being spaced below said flat top walland rigidly connected to the outer edge thereof by a series ofcircumferentially spaced Webs, a disk of larger diameter than said shadeand means for removably securing the ilat top wall of said shade to theunder side of said disk, said disk having a bottom surface adapted toreflect light issuing from the spaces between said circumferentiallyspaced Webs, and the differently tapered portions of said shade havingexterior surfaces adapted to reflect at different angles light reflectedby said bottom surface of said disk.

f DAVID J. BILLER.

